Mercedes-Benz S-Sedan 2015 Owners Manual - Manual (Page 310)

Safety systems
Warning/
indicator
lamp
N N Signal type
Possible causes/consequences and M
M Solutions
$J N $ (USA only), J (Canada only): the red brake system warning lamp
is lit while the engine is running. A warning tone also sounds.
G WARNING
The brake boosting effect is malfunctioning and the braking characteristics
may be affected.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying attention to
road and traffic conditions. Do not continue driving under any circumstan-
ces.
X
Secure the vehicle against rolling away (
Y
page 192).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction display.
$J N $ (USA only), J (Canada only): the red brake system warning lamp
is lit while the engine is running. A warning tone also sounds.
There is not enough brake fluid in the brake fluid reservoir.
G WARNING
The braking effect may be impaired.
There is a risk of an accident.
X
Pull over and stop the vehicle safely as soon as possible, paying attention to
road and traffic conditions. Do not continue driving under any circumstan-
ces.
X Secure the vehicle against rolling away (
Y
page 192).
X Do not add brake fluid. Adding more will not remedy the malfunction.
X
Consult a qualified specialist workshop.
X
Observe the additional display messages in the multifunction display.
308
Warning and indicator lamps in the instrument cluster
On-board
computer
and
displays